Persistent Left Superior Vena Cava in Cardiac Congenital Surgery

Persistent left superior vena cava (LSVC) is a relatively frequent finding in congenital cardiac malformation. The scope of the study was to analyze the timing of diagnosis of persistent LSVC, the timing of diagnosis of associated anomalies of the coronary sinus, and the global impact on morbidity and mortality of persistent LSVC in children with congenital heart disease after cardiac surgery. Retrospective analysis of a cohort of children after cardiac surgery on bypass for congenital heart disease. Three hundred seventy-one patients were included in the study, and their median age was 2.75 years (IQR 0.65-6.63). Forty-seven children had persistent LSVC (12.7 %), and persistent LSVC was identified on echocardiography before surgery in 39 patients (83 %). In three patients (6.4 %) with persistent LSVC, significant inflow obstruction of the left ventricle developed after surgery leading to low output syndrome or secondary pulmonary hypertension. In eight patients (17 %), persistent LSVC was associated with a partially or completely unroofed coronary sinus and in two cases (4 %) with coronary sinus ostial atresia. Duration of mechanical ventilation was significantly shorter in the control group (1.2 vs. 3.0 days, p = 0.04), whereas length of stay in intensive care did not differ. Mortality was also significantly lower in the control group (2.5 vs. 10.6 %, p = 0.004). The results of study show that persistent LSVC in association with congenital cardiac malformation increases the risk of mortality in children with cardiac surgery on cardiopulmonary bypass. Recognition of a persistent LSVC and its associated anomalies is mandatory to avoid complications during or after cardiac surgery.

Combined cardiac and lung volume reduction surgery

Coronary artery disease is prevalent in patients who have severe emphysema and who are being considered for lung volume reduction surgery (LVRS). Significant valvular heart diseases may also coexist in these patients. Few thoracic surgeons have performed LVRS in patients who have severe cardiac diseases. Conversely, few cardiac surgeons have been willing to undertake major cardiac surgery in patients who have severe emphysema. This report reviews the evidence regarding combined cardiac surgery and LVRS to determine the optimal management strategy for patients who have severe emphysema and who are suitable for LVRS, but who also have coexisting significant cardiac diseases that are operable.

Primary prophylaxis for venous thromboembolism in patients undergoing cardiac or thoracic surgery.

BACKGROUND Cardiac and thoracic surgery are associated with an increased risk of venous thromboembolism (VTE). The safety and efficacy of primary thromboprophylaxis in patients undergoing these types of surgery is uncertain. OBJECTIVES To assess the effects of primary thromboprophylaxis on the incidence of symptomatic VTE and major bleeding in patients undergoing cardiac or thoracic surgery. SEARCH METHODS The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched May 2014) and CENTRAL (2014, Issue 4). The authors searched the reference lists of relevant studies, conference proceedings, and clinical trial registries. SELECTION CRITERIA Randomised controlled trials (RCTs) and quasi-RCTs comparing any oral or parenteral anticoagulant or mechanical intervention to no intervention or placebo, or comparing two different anticoagulants. DATA COLLECTION AND ANALYSIS We extracted data on methodological quality, participant characteristics, interventions, and outcomes including symptomatic VTE and major bleeding as the primary effectiveness and safety outcomes, respectively. MAIN RESULTS We identified 12 RCTs and one quasi-RCT (6923 participants), six for cardiac surgery (3359 participants) and seven for thoracic surgery (3564 participants). No study evaluated fondaparinux, the new oral direct thrombin, direct factor Xa inhibitors, or caval filters. All studies had major study design flaws and most lacked a placebo or no treatment control group. We typically graded the quality of the overall body of evidence for the various outcomes and comparisons as low, due to imprecise estimates of effect and risk of bias. We could not pool data because of the different comparisons and the lack of data. In cardiac surgery, 71 symptomatic VTEs occurred in 3040 participants from four studies. In a study of 2551 participants, representing 85% of the review population in cardiac surgery, the combination of unfractionated heparin with pneumatic compression stockings was associated with a 61% reduction of symptomatic VTE compared to unfractionated heparin alone (1.5% versus 4.0%; risk ratio (RR) 0.39; 95% confidence interval (CI) 0.23 to 0.64). Major bleeding was only reported in one study, which found a higher incidence with vitamin K antagonists compared to platelet inhibitors (11.3% versus 1.6%, RR 7.06; 95% CI 1.64 to 30.40). In thoracic surgery, 15 symptomatic VTEs occurred in 2890 participants from six studies. In the largest study evaluating unfractionated heparin versus an inactive control the rates of symptomatic VTE were 0.7% versus 0%, respectively, giving a RR of 6.71 (95% CI 0.40 to 112.65). There was insufficient evidence to determine if there was a difference in the risk of major bleeding from two studies evaluating fixed-dose versus weight-adjusted low molecular weight heparin (2.7% versus 8.1%, RR 0.33; 95% CI 0.07 to 1.60) and unfractionated heparin versus low molecular weight heparin (6% and 4%, RR 1.50; 95% CI 0.26 to 8.60). AUTHORS' CONCLUSIONS The evidence regarding the efficacy and safety of thromboprophylaxis in cardiac and thoracic surgery is limited. Data for important outcomes such as pulmonary embolism or major bleeding were often lacking. Given the uncertainties around the benefit-to-risk balance, no conclusions can be drawn and a case-by-case risk evaluation of VTE and bleeding remains preferable.

Twenty years experience in oncologic surgery for primary cardiac tumors

Introduction. Primary cardiac tumors are uncommon in cardiac surgery. To investigate the clinical presentation, surgical results and long-term follow-up we retrospectively analyzed our experience in the treatment of primary cardiac tumors. Patients and methods. Ninety-one patients with primary cardiac tumors underwent surgery in our department in the last 20 years. Fifthy-one patients were female, the mean age was 62,2 years. Sixty-three had myxomas, 22 had papillary fibroelastoma, 4 had malignant neoformations and 2 had other benign tumors. Results. All myxomas, fibroelastomas and angiomyolipoma were radically removed. Only a palliative treatment was possible in malignant disease. In-hospital mortality was 1.2%. The mean follow-up time was 78.5 months. Three patients had recurrence of myxoma, all patients with malignant disease dead during the follow-up. Discussion. Primary benign cardiac tumors can be treated with low morbidity and mortality. The follow-up demonstrates that radical surgery is curative in case of benign tumors. The prognosis of malignant tumors is still poor. Palliative procedures have small impact on survival in these patients.

Oxygen delivery through high-flow nasal cannulae increase end-expiratory lung volume and reduce respiratory rate in post-cardiac surgical patients

Background: High-flow nasal cannulae (HFNC) create positive oropharyngeal airway pressure but it is unclear how their use affects lung volume. Electrical impedance tomography (EIT) allows assessment of changes in lung volume by measuring changes in lung impedance. Primary objectives were to investigate the effects of HFNC on airway pressure (Paw) and end-expiratory lung volume (EELV), and to identify any correlation between the two. Secondary objectives were to investigate the effects of HFNC on respiratory rate (RR), dyspnoea, tidal volume and oxygenation; and the interaction between body mass index (BMI) and EELV. Methods: Twenty patients prescribed HFNC post-cardiac surgery were investigated. Impedance measures, Paw, PaO2/FiO2 ratio, RR and modified Borg scores were recorded first on low flow oxygen (nasal cannula or Hudson face mask) and then on HFNC. Results: A strong and significant correlation existed between Paw and end-expiratory lung impedance (EELI) (r=0.7, p<0.001). Compared with low flow oxygen, HFNC significantly increased EELI by 25.6% (95% CI 24.3, 26.9) and Paw by 3.0 cmH2O (95% CI 2.4, 3.7). RR reduced by 3.4 breaths per minute (95% CI 1.7, 5.2) with HFNC use, tidal impedance variation increased by 10.5% (95% CI 6.1, 18.3) and PaO2/FiO2 ratio improved by 30.6 mmHg (95% CI 17.9, 43.3). HFNC improved subjective dyspnoea scoring (p=0.023). Increases in EELI were significantly influenced by BMI, with larger increases associated with higher BMIs (p<0.001). Conclusions: This study suggests that HFNC improve dyspnoea and oxygenation by increasing both EELV and tidal volume, and are most beneficial in patients with higher BMIs.

Nurse-led chest drain removal in a cardiac high dependency unit

Within the cardiac high dependency unit it is currently a member of the surgical team who makes the decision for a patient's chest drain to be removed after cardiac surgery. This has often resulted in delays in discharging one patient and therefore in admitting the next. A pilot study was carried out using a working standard that had been developed, incorporating an algorithmic model. The results have enabled nursing staff in a cardiac high dependency unit to undertake this responsibility independently.

Genome-wide association study of perioperative myocardial infarction after coronary artery bypass surgery.

OBJECTIVES: Identification of patient subpopulations susceptible to develop myocardial infarction (MI) or, conversely, those displaying either intrinsic cardioprotective phenotypes or highly responsive to protective interventions remain high-priority knowledge gaps. We sought to identify novel common genetic variants associated with perioperative MI in patients undergoing coronary artery bypass grafting using genome-wide association methodology. SETTING: 107 secondary and tertiary cardiac surgery centres across the USA. PARTICIPANTS: We conducted a stage I genome-wide association study (GWAS) in 1433 ethnically diverse patients of both genders (112 cases/1321 controls) from the Genetics of Myocardial Adverse Outcomes and Graft Failure (GeneMAGIC) study, and a stage II analysis in an expanded population of 2055 patients (225 cases/1830 controls) combined from the GeneMAGIC and Duke Perioperative Genetics and Safety Outcomes (PEGASUS) studies. Patients undergoing primary non-emergent coronary bypass grafting were included. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome variable was perioperative MI, defined as creatine kinase MB isoenzyme (CK-MB) values ≥10× upper limit of normal during the first postoperative day, and not attributable to preoperative MI. Secondary outcomes included postoperative CK-MB as a quantitative trait, or a dichotomised phenotype based on extreme quartiles of the CK-MB distribution. RESULTS: Following quality control and adjustment for clinical covariates, we identified 521 single nucleotide polymorphisms in the stage I GWAS analysis. Among these, 8 common variants in 3 genes or intergenic regions met p<10(-5) in stage II. A secondary analysis using CK-MB as a quantitative trait (minimum p=1.26×10(-3) for rs609418), or a dichotomised phenotype based on extreme CK-MB values (minimum p=7.72×10(-6) for rs4834703) supported these findings. Pathway analysis revealed that genes harbouring top-scoring variants cluster in pathways of biological relevance to extracellular matrix remodelling, endoplasmic reticulum-to-Golgi transport and inflammation. CONCLUSIONS: Using a two-stage GWAS and pathway analysis, we identified and prioritised several potential susceptibility loci for perioperative MI.

Platelet Counts, Acute Kidney Injury, and Mortality after Coronary Artery Bypass Grafting Surgery.

BACKGROUND: Cardiac surgery requiring cardiopulmonary bypass is associated with platelet activation. Because platelets are increasingly recognized as important effectors of ischemia and end-organ inflammatory injury, the authors explored whether postoperative nadir platelet counts are associated with acute kidney injury (AKI) and mortality after coronary artery bypass grafting (CABG) surgery. METHODS: The authors evaluated 4,217 adult patients who underwent CABG surgery. Postoperative nadir platelet counts were defined as the lowest in-hospital values and were used as a continuous predictor of postoperative AKI and mortality. Nadir values in the lowest 10th percentile were also used as a categorical predictor. Multivariable logistic regression and Cox proportional hazard models examined the association between postoperative platelet counts, postoperative AKI, and mortality. RESULTS: The median postoperative nadir platelet count was 121 × 10/l. The incidence of postoperative AKI was 54%, including 9.5% (215 patients) and 3.4% (76 patients) who experienced stages II and III AKI, respectively. For every 30 × 10/l decrease in platelet counts, the risk for postoperative AKI increased by 14% (adjusted odds ratio, 1.14; 95% CI, 1.09 to 1.20; P < 0.0001). Patients with platelet counts in the lowest 10th percentile were three times more likely to progress to a higher severity of postoperative AKI (adjusted proportional odds ratio, 3.04; 95% CI, 2.26 to 4.07; P < 0.0001) and had associated increased risk for mortality immediately after surgery (adjusted hazard ratio, 5.46; 95% CI, 3.79 to 7.89; P < 0.0001). CONCLUSION: The authors found a significant association between postoperative nadir platelet counts and AKI and short-term mortality after CABG surgery.

Streptococcus bovis bacteraemia: an evaluation of the long-term effect on cardiac outcomes

Introduction: Streptococcus bovis can lead to bacteraemia, septicaemia, and ultimately endocarditis. The objective of this study was to evaluate the long-term implications of S. bovis endocarditis on cardiac morbidity and mortality. 

Methods: A retrospective cohort study was performed between January 2000 and March 2009 to assess all patients diagnosed with S. bovis bacteraemia from the Belfast Health and Social Care Trust. The primary end-point for cardiac investigations was the presence of endocarditis. Secondary end-points included referral for cardiac surgery and overall mortality. 

Results: Sixty-one positive S. bovis blood cultures from 43 patients were included. Following echocardiography, seven patients were diagnosed with infective endocarditis (16.3 % of total patients); four patients (9.3 %) had native valve involvement while three (7.0 %) had prosthetic valve infection. Five of these seven patients had more than one positive S. bovis culture (71.4 %). Three had significant valve dysfunction that warranted surgical repair/replacement, one of whom was unfit for surgery. There was a 100 % recurrence rate amongst the valve replacement patients (n = 2) and six patients with endocarditis had colorectal pathology. Patients with endocarditis had similar long-term survival as those with non-endocarditic bacteraemia (57.1 % alive vs. 50 % of non-endocarditis patients, p = 0.73). 

Conclusion: Streptococcus bovis endocarditis patients tended to have pre-existing valvular heart disease and those with prosthetic heart valves had higher surgical intervention and relapse rates. These patients experienced a higher rate of co-existing colorectal pathology but currently have reasonable long-term outcomes. This may suggest that they represent a patient population that merits consideration for an early surgical strategy to maximise long-term results, however, further evaluation is warranted. © 2013 The Japanese Association for Thoracic Surgery.

Impact of early valve surgery on outcome of Staphylococcus aureus prosthetic valve infective endocarditis: analysis in the International Collaboration of Endocarditis-Prospective Cohort Study.

BACKGROUND: The impact of early valve surgery (EVS) on the outcome of Staphylococcus aureus (SA) prosthetic valve infective endocarditis (PVIE) is unresolved. The objective of this study was to evaluate the association between EVS, performed within the first 60 days of hospitalization, and outcome of SA PVIE within the International Collaboration on Endocarditis-Prospective Cohort Study. METHODS: Participants were enrolled between June 2000 and December 2006. Cox proportional hazards modeling that included surgery as a time-dependent covariate and propensity adjustment for likelihood to receive cardiac surgery was used to evaluate the impact of EVS and 1-year all-cause mortality on patients with definite left-sided S. aureus PVIE and no history of injection drug use. RESULTS: EVS was performed in 74 of the 168 (44.3%) patients. One-year mortality was significantly higher among patients with S. aureus PVIE than in patients with non-S. aureus PVIE (48.2% vs 32.9%; P = .003). Staphylococcus aureus PVIE patients who underwent EVS had a significantly lower 1-year mortality rate (33.8% vs 59.1%; P = .001). In multivariate, propensity-adjusted models, EVS was not associated with 1-year mortality (risk ratio, 0.67 [95% confidence interval, .39-1.15]; P = .15). CONCLUSIONS: In this prospective, multinational cohort of patients with S. aureus PVIE, EVS was not associated with reduced 1-year mortality. The decision to pursue EVS should be individualized for each patient, based upon infection-specific characteristics rather than solely upon the microbiology of the infection causing PVIE.

Influence of fresh frozen plasma as a trigger factor for kidney dysfunction in cardiovascular surgery

OBJETIVO: A disfunção renal é uma complicação importante no cenário de pós-operatório de cirurgia cardiovascular. Como fatores de risco conhecidos no intraoperatório para o seu desenvolvimento destacam-se a circulação extracorpórea, a hemodiluição, drogas antifibrinolíticos e a transfusão sanguínea. O objetivo deste estudo é identificar os fatores de risco na transfusão de sangue e derivados para o desenvolvimento de disfunção renal em pacientes submetidos à cirurgia cardiovascular. MÉTODOS: Noventa e sete pacientes foram estudados e 84 foram analisados. A amostra foi estratificada em dois grupos, sendo que o incremento de 30% na creatinina sérica no pós-operatório foi considerado para o grupo com disfunção renal (n = 9; 10,71%). O grupo não disfunção renal foi caracterizado pela creatinina sérica, que permaneceu inferior a aumento de 30% no pós-operatório (n = 75; 89,28%). RESULTADOS: Foi observado que a transfusão de plasma fresco congelado no grupo não disfunção renal foi de 2,05 ± 0,78 unidades e 3,80 ± 2,16 unidades no grupo disfunção renal com P= 0,032. CONCLUSÃO: Foi possível associar, nesta série de pacientes, que a transfusão de plasma fresco congelado foi um fator de risco para disfunção renal pós-operatório de cirurgia cardiovascular.

Predicted preoperative maximal static respiratory pressures in adult cardiac surgeries: evaluation of two formulas

Objectives: Cardiac surgery (CC) determines systemic and pulmonary changes that require special care. What motivated several studies conducted in healthy subjects to assess muscle strength were the awareness of the importance of respiratory muscle dysfunction in the development of respiratory failure. These studies used maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) values. This study examined the concordance between the values predicted by the equations proposed by Black & Hyatt and Neder, and the measured values in cardiac surgery (CS) patients. Methods: Data were collected from preoperative evaluation forms. The Lin coefficient and Bland-Altman plots were used for statistical concordance analysis. The multiple linear regression and analysis of variance (ANOVA) were used to produce new formulas. Results: There were weak correlations of 0.22 and 0.19 in the MIP analysis and of 0.10 and 0.32 in the MEP analysis, for the formulas of Black & Hyatt and Neder, respectively. The ANOVA for both MIP and MEP were significant (P <0.0001), and the following formulas were developed: MIP = 88.82 - (0.51 x age) + (19.86 x gender), and MEP = 91.36 -(030 x age) + (29.92 x gender). Conclusions: The Black and Hyatt and Neder formulas predict highly discrepant values of MIP and MEP and should not be used to identify muscle weakness in CS patients.

Age influences outcomes in 70-year or older patients undergoing isolated coronary artery bypass graft surgery

Objective: To analyze the results of isolated on-pump coronary artery bypass graft surgery (CABG) in patients >= 70 years old in comparison to patients <70 years old. Methods: Patients undergoing isolated CABG were selected for the study. The patients were assigned into two groups: G1 (age >= 70 years old) and G2 (age <70 years old). The endpoints were in-hospital mortality, acute myocardial infarction (AMI), stroke, re-exploration for bleeding, intraaortic balloon pump for circulatory shock, respiratory complications, acute renal failure, mediastinitis, sepsis, atrial fibrillation, and complete atrioventricular block (CAVB). Results: A total of 1,033 were included in the study: G1 comprised 257 (24.8%) patients G2 776 (75.2%). Patients in G1 were more likely to have in-hospital mortality than in G2 (8.9% vs. 3.6%, respectively; P=0.001), while the incidence of AMI was similar (5.8% vs. 5.5%; P=0.87) in G2. More patients in G1 had re-exploration for bleeding (12.1% vs. 6.1%; P=0.003). Compared to G2, G1 had more incidences of respiratory complications (21.4% vs. 9.1%; P<0.001), mediastinitis (5.1% vs. 1.9%; P=0.013), stroke (3.9% vs. 1.3%; P=0.016), acute renal failure (7.8% vs. 1.3%; P<0.001), sepsis (3.9% vs. 1.9%; P=0.003), atrial fibrillation (15.6% vs. 9.8%; P=0.016), and CAVB (3.5% vs. 1.2%; P=0.023). There was no significant difference in the use of the intraaortic balloon pump. In the forward stepwise multivariate logistic regression analysis, age >= 70 years was an independent predictive factor for higher in-hospital mortality (P=0.004), re-exploration for bleeding (P=0.002), sepsis (P=0.002), respiratory complications (P<0.001), mediastinitis (P=0.016), stroke (P=0.029), acute renal failure (P<0.001), atrial fibrillation (P=0.021), and CAVB (P=0.031). Conclusion: This study suggests that patients of age >= 70 years were at increased risk of death and other complications in the CABG's postoperative period in comparison to younger patients.

Influence of cardiopulmonary bypass on cefuroxime plasma concentration and pharmacokinetics in patients undergoing coronary surgery

The aims of this study were to evaluate the influence of cardiopulmonary bypass (CPB) on the plasma concentrations and pharmacokinetics of cefuroxime and to assess whether the cefuroxime dose regimen (a 1.5 g dose, followed by 750 mg every 6 h for 24 h) is adequate for cardiac surgery antibiotic prophylaxis. A prospective, controlled, observational study compared patients undergoing coronary surgery with CPB (CPB group, n = 10) or off-pump surgery (off-pump group, n = 9). After each cefuroxime dose, blood samples were sequentially collected and analysed using high-efficiency chromatography. For demographic data and pharmacokinetic parameters, the authors used Fisher's exact test for nominal variables and Student's t-test and the Mann-Whitney U-test for parametric and non-parametric variables, respectively. Plasma concentrations were compared using ANOVA, and the percentage of patients with a remaining plasma concentration of > 16 mg/l within 6 h after each bolus was quantified in tabular form. After each cefuroxime bolus was administered, both groups presented a significant decrease in plasma concentration over time (P < 0.001), without differences between the groups. The mean CPB time of 59.7 +/- 21.1 min did not change cefuroxime plasma concentrations or pharmacokinetics. The mean clearance +/- SD (ml/kg/min) and median elimination half-life (h) of the CPB group versus the off-pump group were 1.7 +/- 0.7 versus 1.6 +/- 0.6 (P = 0.67), respectively, and 2.2 versus 2.3 (P = 0.49), respectively. Up to 3 h following the first bolus of 1.5 g, but not after 6 h, all patients had plasma concentrations > 16 mg/l (CPB group = 20% and off-pump group = 44%). However, after all 750 mg boluses were administered, concentrations < 16 mg/dl were reached within 3 h. CPB does not influence cefuroxime plasma concentrations. The dosing regimen is adequate for the intraoperative period, but in the immediate postoperative period, it requires further review.